Wall plate for electrical devices



' Aug. 27, 1935. M, GUETT 2,012,875

`,WALL PLATE FOR ELECTRICAL DEVICES Filed June 30, 1935 le Ti'l' 3 l I |o l6` HHIIIIIIIHHHHIII HHHHHHH la 24 2e 2a C) la 22 y 2o a j P ll NHHHHIH lllllll j' I4 INVENTOR MONROE GUETT BY His ATTORNEYS Patented Aug. 27, 1935 WALL PLATE FOR ELECTRICAL "DEVICES Monroe Guett, Hartford, Conn., assignor to The Arrow-Hart & Hegeman Electric Company, Hartford, Conn., a corporation of Connecticut Application June 30, 1933, Serial No. 678,520

3 Claims.

This invention relates to wall plates for such electrical devices as attachment plug receptacles, switches and pilot lights and the like.

More particularly this invention relates to wall 5 plates such as are commonly used to cover electrical devices oi' the above types which are mounted in outlet boxes, these wall plates serving the dual purpose of covering the wiring device and acting as an ornament.

' When several electric attachment plug receptacles or other wiring devices are mounted in a single gang outlet box in interchangeable relation by suitable means such as is shown in my Patent No. 1,909,270, danger of a short circuit is encountered in inserting an attachment plug cap into a receptacle by reason of the fact that the aperture in which the receptacle casing is mounted is so narrow that the screws of the binding terminals in the attachment plug cap, or

a strand of the wire connected thereto, can bridge apertures if the screws or strand of wire project beyond the plane of the lower face of the attachment plug cap. Thus, if an all metal plate is used, a short circuit may occur. But in some cases it is desirable to have a metal plate for the particular ornamental effect which it may give and in such a situation a plate made entirely of insulation would be unsuitable.

It is an object of my invention to provide a face plate with the ornamentality of a metal plate and the insulating qualities of an insulating plate.

Another object of my invention is to provide a metal plate with suitable insulating means, such as an escutcheon or insert of insulating material, to prevent short circuiting when an attachment plug cap is inserted into a receptacle of the above type mounted behind said plate.

Other objects and advantages of my invention will become apparent as it is described in connection with the accompanying drawing:-

In the drawing:-

Figure l is a plan view of a metal face plate with a bakelite escutcheon formed according to the principles of my invention.

Figure 2 is a longitudinal section view taken on the line 2-2 of Figure 1.

Figure 3 is a transverse section view taken on the line 3-3 of Figure 1.

Figure 4 is a rear view of the plate shown in Figure 1.

Referring to the drawing a face plate I0 made of brass or other metal may be stamped or cast in the usual size to cover a conventional wall or 65 outlet box end this plete may be provided with a beveled edge or ange I2, according to common practice.

A rectangular aperture I4 is formed in the center of the plate, the periphery of this aperture being raised or pressed out of the plate form- 5 ing an oilset or bead I6. The corners of the aperture I4 may be rounded for ornamental cect, and to give added strength. Into the aperture I4 may be pressed and frictionally held an escutcheon I8 formed of bakelite or other 10 insulating material, this escutcheon having a plurality of apertures 20, 22, 24 separated from one another by cross bars 26 and 28. 'I'he longer sides of the escutcheon are provided with ledges or shoulders 30 extending the full length of the 15 long sides. 'I'he escutcheon is dimensioned so as to t tightly and to be held by friction within the aperture I4 with the iiange 30 of the escutcheon resting against the rear surface of the odset or bead I6. 20

The rear face of the escutcheon may be recessed around the apertures 20, 22 and 24 to form shoulders 40 which may abut complementary shoulders 42 upon the insulation casing of an electric wiring device 44 which in the example 25 shown in Figure 2 is an attachment plug receptacle. Obviously other electric wiring devices such as switches or pilot lights may be accommodated within casings of similar size and shape to the casing 44 and may be placed in any one of 30 the apertures 20, 22 and 24. The electric wiring devices will commonly be mounted upon a supporting bridge and may be secured thereon and to an outlet or wall box by the means shown in my Patent No. 1,909,270. 35

It will be observed that due to the limited dimensions that may be allowed the electric wiring devices, when several of them are to be placed in a single gang wall box and covered by a single gang wall plate, that the binding screws 50 upon 40 the feet or terminals of the prongs 52 of a conventional standard sized attachment plug cap 54, will extend beyond the edges of the casing of the wiring devices. If it should happen that one or both of the screws 50 were not screwed in 46 tightly or a strand of the connecting wires 58 became loose, either the strand or the binding screws might touch the side bars 26 and 28 in case the cap was being inserted in a receptacle positioned in aperture 22. Or if the cap were 50 being inserted in a receptacle positioned in aperture 20 or 24, the strand or loose screw might touch one of the side bars and the material surrounding the aperture 20 or 24. By reason of the escutcheon being made of insulating material this 55 contact of the screw or strand of wire with it is harmless but if the plate were made in one piece of metal a short circuit might result. Thus, it will be seen that I have provided a face plate which has the desirable ornamental characteristics of an ordinary brass face plate and at the same time it possesses the insulating qualities of face plates made entirely of insulating material.

The invention can be applied to face plates generally whether one, two, or more wiring devices are to be accommodated, so long as there is adherence to the principal that the escutcheon be at least as wide as the distance between the binding screws of a conventional attachment plug cap. Thus it will be apparent that the three aperture single gang plate shown is merely an example chosen for the purpose of illustration.

Many other forms of my invention will occur to those skilled in the art; therefore I do not limit the invention to the speciiic embodiment shown. Thus it will be observed that the escutcheon can be made to fit loosely within the aperture of the metal plate, It would, in that case, be held there (resting on the shoulders 42 of any wiring devices which might be mounted on a supporting strap as shown in my Patent 1,909,270) by the face plate, which would be secured in any conventional manner over the outlet box.

I claim:-

1. In combination, a metallic face plate for electric wiring devices, an insulating escutcheon within an aperture in said plate, and an attachment plug receptacle received in an aperture ln said escutcheon, said receptacle being adapted for reception of the prongs of a conventional attachment plug cap having spaced wire terminals exposed on the underside thereof, the distance between the opposite walls defining the aperture in the metallic face plate being greater than the distance between the spaced wire terminals on the underside of the attachment plug cap, and the distance between opposite walls dening the aperture in the escutcheon and surrounding the receptacle being less than the distance between said spaced wire terminals, whereby said wire terminals are insulated from said metallic face plate by said insulating escutcheon.

2. In combination, a metallic face plate for electric wiring devices, an insulating escutcheon within an aperture in said plate, said escutcheon having a ledge engaging the under side of said plate, an electric wiring device received Within an aperture in said escutcheon whereby said escutcheon is held between said wiring device and said plate.

3. A cover for an electric wiring device comprising a metallic plate having an aperture, an insulating escutcheon fitting within said aperture and having an aperture within it for receiving an electric wiring device, said escutcheon having a portion lying beneath said plate whereby said escutcheon is held in place between the wiring device and said plate.

MONROE GUETT. 

